PRIN. OF INTERNAL COMBUSTION ENGINES - OD1619 LESSON 1/TASK 2
FIGURE 33.
COMPARISON OF TWO AND
FOUR STROKE CYCLE DIESEL
POWER STROKE LENGTHS.
4.
Combustion Chamber Design
a. General.
The fuel injected into the combustion chamber must be mixed
thoroughly with the compressed air and be distributed as evenly as possible
throughout the chamber if the engine is to function at maximum driveability. The
well-designed diesel engine uses a combustion chamber that is designed for the
engine's intended usage.
The injectors used in the engine should compliment the
combustion chamber.
The combustion chambers described in the following
subparagraphs are the most common and cover virtually all of the designs that are
used in current automotive applications.
b. Open Chamber (figure 34 on the following page).
The open chamber is the
simplest form of chamber.
It is suitable for slow-speed, four stroke cycle
engines, and is used widely in two stroke cycle diesel engines.
In the open
chamber, the fuel is injected directly into the space at the top of the cylinder.
The combustion space, formed by the top of the piston and the cylinder head, is
usually shaped to provide a swirling action of the air as the piston comes up on
the compression stroke.
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